Foot joined the staff of Lord Mountbatten at the headquarters of Combined Operations before training as an officer in the Special Air Service (SAS). In 1944 he was appointed intelligence officer in the SAS brigade.

According to the military historian, Brian Bond: "In August 1944 he was flown into Brittany in a vain attempt to eliminate a notorious Gestapo officer. He was taken prisoner, resisted torture and managed to escape, only to be savagely beaten and left for dead by the French peasants in whose farm he and a comrade had tried to shelter. Recaptured, he was fortunate to be repatriated soon afterwards in exchange for a U-boat commander." Foot later recalled that during the war he had "been shot at, have parachuted, have helped to plan raids, have taken part as observer in air operations and in a sea commando raid and have organised escapes." In 1945 he was awarded the Croix de Guerre for service with the French Resistance.

Foot eventually entered the Cabinet Office as an official historian. In 1958 Harold Macmillan authorised him to carry out research into Special Operations Executive (SOE). According to The Daily Telegraph: "There were, his interviewers told him, some conditions: he was not allowed to tell anyone what he was doing - not even his wife. He was, furthermore, to write his account on the assumption that MI6 did not exist, and without the knowledge or co-operation of the men and women involved. Few historians can have embarked on their magnum opus so circumscribed as Foot. For two years he ferreted through the secret files held in the Foreign Office and Cabinet Office, some so secret that when reading them he had to be locked in a room in a Whitehall basement, from which he could escape only by ringing a bell. He was also hampered by the fact that many of SOE’s files had been destroyed, and others were available only if he specifically requested them; moreover, he had no access to French archives."

Foot's friend, Brian Bond, has pointed out: "Foot was a strikingly handsome man with intense intellectual energy and a remarkable fund of anecdotes and arcane information – imparted in a clipped, precise and almost lapidary style. He abhorred dullness and prolixity, and in seminars and conversation his ability to sparkle and stimulate ideas was unfailing. Following his father's advice he vowed never to retire and remained active, in research, writing and attending academic meetings until the final weeks of his life."

Primary Sources

The genesis of Foot’s classic account SOE in France (1966) was almost as clandestine as its subject. In 1958 the Prime Minister, Harold Macmillan, authorised the inception of research, but it was not until two years later that Foot was invited to an interview in the Foreign Office. Even then, it was only after an hour-long grilling that he was asked whether he would like to take on such a project.

There were, his interviewers told him, some conditions: he was not allowed to tell anyone what he was doing - not even his wife. He was, furthermore, to write his account on the assumption that MI6 did not exist, and without the knowledge or co-operation of the men and women involved.

Few historians can have embarked on their magnum opus so circumscribed as Foot. For two years he ferreted through the secret files held in the Foreign Office and Cabinet Office, some so secret that when reading them he had to be locked in a room in a Whitehall basement, from which he could escape only by ringing a bell. He was also hampered by the fact that many of SOE’s files had been destroyed, and others were available only if he specifically requested them; moreover, he had no access to French archives.

By Christmas 1962 he had finished the first draft, only to see it disappear into the bowels of the Foreign Office. He heard nothing more for well over a year, until April 1964, when Peter Thomas, Minister of State at the Foreign Office, announced that a draft of the history had been completed and that the government had decided in principle that it should be published by Her Majesty’s Stationery Office.

This intelligence came as a complete surprise to former SOE hands, including Colonel Maurice Buckmaster and Major-General Sir Colin Gubbins, who had been in charge of SOE’s operations in France at the time. Though disconcerted, both men agreed to help, and, on their advice and that of other old SOE hands, Foot made further revisions to the draft.

Even so, when the book was finally published, it aroused enormous controversy for its portrayals of some SOE operatives; half a dozen former agents threatened legal action and there were two successful libel suits.

Yet for all the difficulties involved, Foot’s account was acclaimed as a classic, and he was widely praised for the skill with which he linked the experience of agents on the ground with the organisational and geographical handicaps of controllers back in London. While he did not try to disguise its occasional failures, he defended SOE against charges of inefficiency and callousness, paying tribute to its role in helping to restore French self-respect by its support of the Resistance movement.

Foot was a strikingly handsome man with intense intellectual energy and a remarkable fund of anecdotes and arcane information – imparted in a clipped, precise and almost lapidary style. He abhorred dullness and prolixity, and in seminars and conversation his ability to sparkle and stimulate ideas was unfailing. Following his father's advice he vowed never to retire and remained active, in research, writing and attending academic meetings until the final weeks of his life.